The invention relates generally to a method of forming integrated waveguide cavities and in particular to such a method for millimeter-wave, solid-state modules.
The dimensions of waveguide cavities are dependent upon the size of the wave they are required to handle. The longer the wave the larger the hardware needed to move the wave from one location to another, and in general the greater the tolerances and the lower the cost of the equipment. On the other hand, at millimeter-wave frequencies the waveguide cavity dimensions become so small that the cost of machining parts with the required tolerances is very high.
The conventional approach to the problem of manufacturing waveguides in the millimeter range is to machine the waveguide and then mount the solid-state module i.e., a millimeter-wave solid state diode mounted in a separate cavity. Another disadvantage to the conventional process of fabrication is that solid state devices are generally formed with a large number on a single wafer which must then be cut and the individual device incorporated into the waveguide. The smaller the dimensions of the individual pieces the higher the reject rate in the quality control process.
It is therefore more advantageous and less expensive to manufacture a large number of devices having larger dimensions and cut and separate after the manufacturing process is completed.